LAB · FREE

Take a question. Try a rule.

Change a simple rule and replay a fictional market. See every decision, count the costs, and compare with cash and holding.

Try a lesson rule

No account needed. Made-up inputs, simulated money.

Make one change

Adjust the daily threshold or the fee on each side. Read the exact rule before you run it.

Inspect what happened

Follow buys, waits, exits and missing observations. A higher return alone cannot establish a useful strategy.

Keep your reasoning

Save a replay on this device or download its results and your explanation. Saved runs preserve the settings you used.

Already have a member account?

The member workspace keeps your theoretical accounts and rule drafts. The new replay saves separately on this device. Passkey accounts have no recovery process yet.

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